From: Eric Blake <ebl...@redhat.com> nbd-server.c currently fails to handle unsupported options properly. If during option haggling the client sends an unknown request, the server kills the connection instead of letting the client try to fall back to something older. This is precisely what advertising NBD_FLAG_FIXED_NEWSTYLE was supposed to fix.
Signed-off-by: Eric Blake <ebl...@redhat.com> Message-Id: <1459982918-32229-1-git-send-email-ebl...@redhat.com> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- nbd/server.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/nbd/server.c b/nbd/server.c index 6d9c15a..2a4dd10 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -483,9 +483,12 @@ static int nbd_negotiate_options(NBDClient *client) return -EINVAL; default: TRACE("Unsupported option 0x%x", clientflags); + if (nbd_negotiate_drop_sync(client->ioc, length) != length) { + return -EIO; + } nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_UNSUP, clientflags); - return -EINVAL; + break; } } else { /* -- 2.5.5